Offline progress got lost

I was playing pvz 2 from a long time offline and completed many levels. So last night I decided to save my progress by connecting it to my google game play account.

After doing that, in the next morning I open the game and found that all my progress got dissappeared. I tried to reconnect my account with google play and also sync it but my old progress is not recovering.

How do I recover my offline progress? And plz don't tell me that I have to restart the game now. (also sorry for bad english)